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51.
Frame-based stereotactic body radiation therapy (SBRT), such as that conducted with Elekta's Stereotactic Body Frame, can provide an extra measure of precision in the delivery of radiation to extracranial targets, and facilitates secure patient immobilization. In this paper, we review the steps involved in optimal use of an extra-cranial immobilization device for SBRT treatments. Our approach to using frame-based SBRT consists of 4 steps: patient immobilization, tumor and organ motion control, treatment/planning correlation, and daily targeting with pretreatment quality assurance. Patient immobilization was achieved with the Vac-Loc bag, which uses styrofoam beads to conform to the patient's shape comfortably within the body frame. Organ and motion control was assessed under fluoroscopy and controlled via a frame-mounted abdominal pressure plate. The compression screw was tightened until the diaphragmatic excursion range was < 1 cm. Treatment planning was performed using the Philips Pinnacle 6.2b system. In this treatment process, a 20 to 30 noncoplanar beam arrangement was initially selected and an inverse beam weight optimization algorithm was applied. Those beams with low beam weights were removed, leaving a manageable number of beams for treatment delivery. After planning, daily targeting using computed tomography (CT) to verify x-, y-, and z-coordinates of the treatment isocenter were used as a measure of quality assurance. We found our daily setup variation typically averaged < 5 mm in all directions, which is comparable to other published studies on Stereotactic Body Frame. Treatment time ranged from 30 to 45 minutes. Results demonstrate that patients have experienced high rates of local control with acceptable rates of severe side effects - by virtue of the tightly constrained treatment fields. The body frame facilitated comfortable patient positioning and quality assurance checks of the tumor, in relation to another set of independent set of coordinates defined by the body frame fiducials. The ability to impose abdominal compression proved to be a simple way to reduce target and tissue motion. SBRT with Stereotactic Body Frame enables comfortable patient immobilization and facilitates repeated registering and re-registering of the patient to the frame. With the body frame, large-dose-per fraction treatment is possible for localized tumor deposits with the aim of attaining a more therapeutic result. 相似文献
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At birth the human newborn is immature and has not yet acquired fully competent organ functions. During lactation especially the digestive tract and the immune system gain competence. Lactation is regulated by a complex interaction of numerous hormonal factors. Most important are probably prolactin and oxytocin—two hormones produced and secreted in the pituitary. The production and secretion of these two hormones is again regulated by several factors in the central nervous system and these mechanisms can be disturbed by a variety of exogenous factors such as drugs and any other substances interacting with dopamine metabolism in the brain. It is important to know these physiological interactions to be able to understand the regulation of lactation and to be able to assess which factors could interfere with this process. 相似文献
54.
PD Dr. M.W. Strik S. Anders M. Barth E. Bärlehner C. Benecke T. Benhidjeb 《Der Chirurg》2007,78(12):1139-1144
BACKGROUND: The axillobilateral breast approach (ABBA) is a procedure allowing thyroid resection without scarring at the neck. We operated on a series of 26 patients with this technique. METHOD: Via incisions at the edge of the mamilla and axilla, trocars are placed subcutaneously under the platyma. Dissection is performed bluntly and with an ultrasonographic scalpel under videoscopic control. The procedure itself corresponds to conventional surgery. The specimen is removed through the axillary trocar. RESULTS: Twenty-six female patients underwent thyroid resection using the ABBA technique. Subtotal resection was performed in 24. Mean operation times were 111 min (unilateral) and 187 min (bilateral). In none of these cases was conversion necessary. One transient recurrent laryngeal nerve palsy and one paresis of the arm plexus were found postoperatively. CONCLUSION: In selected patients the ABBA technique is feasible and safe with the mandatory radicalness. The primary aim of this method is the cosmetic result. 相似文献
55.
PD Dr. B. Clasbrummel B. Jettkant N. DeLuca G. Muhr G. Möllenhoff 《Trauma und Berufskrankheit》2007,9(2):84-87
The life time of hip endoprostheses is in part limited by aseptic loosening. The aim of this study was to produce a digital system for recording shaft loosening in such endoprostheses using acceleration sensors. Four identical prosthetic shafts were each set with 3.2-axial acceleration sensors and placed in artificial femurs. In order to simulate a firm fit, one prosthesis was fixed with bone cement; a loose fit was fixed with a surrounding silicon shell 0.5 mm thick. Simulation of the transition from firm to loose in the other two prostheses was attained by the distal 2/3 or 1/3 being cemented, with the rest surrounded by a silicone shell. A weak oscillation was initiated via a damped falling weight. Using a fast Fourier transformation it was possible to make a global evaluation of the measurement curves. A wavelet transformation could be used to differentiate firm or loose prostheses. A third order Daubechies filter recognized the deviation in the main oscillation, made visible by an increase in amplitude. The results encourage the development of an implantable, telemetrically functioning total system which would allow digital quality assurance when integrated into the endoprosthesis. 相似文献
56.
PD Dr. A. Gries N. Russ G. Conrad Ch. Müller-Ramcke J. Braun 《Notfall & Rettungsmedizin》2007,10(2):137-143
The 2006, annual meeting of the senior physicians and emergency medical technicians of the German Air Rescue Service (Deutschen Rettungsflugwacht, DRF) was titled “From Concept to Practice”. The themes of security in the air rescue services and the current practice of cardiopulmonary respiration were discussed. In addition, different concepts and networks for treating patients with acute coronary syndrome or severe trauma were presented. The training of emergency technicians and quality assessment using the database of the whole TeamDRF was explained. New helicopter stations as well as long-range transport using normal aviation by the TeamDRF were presented. 相似文献
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Mechanism of Pseudomonas aeruginosa persistence during treatment with broad-spectrum cephalosporins of lung infections in patients with cystic fibrosis. 总被引:1,自引:0,他引:1 下载免费PDF全文
A B Schryvers J Ogunariwo S Chamberland A J Godfrey H R Rabin L E Bryan 《Antimicrobial agents and chemotherapy》1987,31(9):1438-1439
Beta-lactam resistance in Pseudomonas aeruginosa detected only during ceftazidime therapy of cystic fibrosis patients was studied. Evaluation of resistant and susceptible isolates from one patient and resistant laboratory derivatives indicated that elevated beta-lactamase levels were the primary determinant of resistance. Susceptible isolates outgrew resistant isolates on antibiotic-free medium. 相似文献
60.
PD Dr. R. Voll 《Monatsschrift für Kinderheilkunde》2006,154(8):810-816
The guidelines regarding medical rehabilitation have changed. When applying for medical rehabilitation, the International Classification of Functioning (ICF) must be used for young adults with somatic and/or psychiatric diseases. The ICF is an appropriate tool to assess the outcome of rehabilitation in children and adolescents. Nowadays the ICF is used in rehabilitation hospitals; in former times the Functional Independence Measure (FIM) was used. The different criteria of the ICF such as personal factors, environmental factors, body function and structure (impairment), activities (limitation) and participation (restriction) are explained. A case report is presented which shows the outcome of rehabilitation according to FIM and ICF in graphic form. 相似文献